[Risk factors for retinal occlusive diseases].

Retinal vascular occlusions are the second most common retinal vascular diseases following diabetic retinopathy. Central retinal artery occlusion and branch retinal artery occlusion are most often caused by emboli. The mean age of patients with retinal artery occlusion and branch retinal artery occlusion is 62 and 58 years, respectively. The most common risk factors are arterial hypertension (65%), diabetes mellitus (25%), valvular diseases of the heart (25%), and carotid artery stenosis or plaques (45%). Rare causes are arteritis and vascular spasm. The pathogenesis of retinal branch vein occlusion and central retinal vein occlusion remains speculative. Two different mechanisms have been postulated, i.e. thrombosis in the vein due to a compression by atherosclerotic changes in the adjacent artery and a local alteration of the blood flow due to unfavourable physiologic factors. Retinal vein occlusion manifests at a mean age of 65 years. The most common risk factors are arterial hypertension in 34-75% and primary open angle glaucoma in 2.1-82%. In 5.6% of the patients with retinal branch vein occlusion retinal vasculitis is present.